1. Field of the Invention
This invention relates to a data transmission system, and more particularly to a data transmission method and apparatus for a mobile radiocommunication system.
2. Description of the Related Art
In conventional mobile radiocommunication systems, either of two methods of realizing error-free data transmission are employed: forward error correction (hereinafter referred to as FEC) wherein self correction is performed; or automatic repeat request (hereinafter referred to as ARQ) wherein a request for transmission of data is repeated at the transmission side when a transmission error of data occurs at the reception side.
The conventional data transmission systems described above have different disadvantages. The FEC is disadvantageous in that, in a radio section in which the transmission characteristics are good, transmission efficiency by FEC is low, and the ARQ is disadvantageous in that the transmission efficiency is low in a radio communication section in which the transmission characteristics are poor due to the very significant increase in the number of repeats of data transmission.